This core will provide basic nucleic acid and recombinant DNA procedures for the program project. It will provide equipment and personnel specifically for the growth and isolation of plasmids or bacteriophage containing cloned DNA and for DNA sequencing. All of the projects will make use of this core. A major rationale for the establishment of this core was that the large volume of plasmid preparation envisioned by Project 3 required the purchase of an additional ultracentrifuge. By placing this item in a core facility along with other items needed for plasmid preparation, other investigators will have the benefit of the equipment and personnel. This core will also provide a DNA sequencing service for the program project as a whole. By providing specialized equipment, techniques and personnel, this core will increase the efficiency of the program project.